Biological activity of Ipomoea pauciflora Martens and Galeotti (Convolvulaceae) extracts and fractions on larvae of Spodoptera frugiperda J. E. Smith (Lepidoptera: Noctuidae)

Hexane, chloroform and methanol extracts of different parts of Ipomoea pauciflora were tested for their effects on the survival and development of Fall Armyworm (Spodoptera frugiperda), a Lepidoptera pest. For seven days, neonatal larvae (grown at 27 ± 2°C with a 16: 8 (L: D) h photoperiod) were exposed to different concentrations of crude I. pauciflora extracts (ranging from 0 to 4 mg/ml) that were incorporated into an artificial diet. Surviving larvae were weighed at days 6, 9 and 13 and were maintained until moths emerged. Eleven of the 18 crude extracts showed more than 30% larval mortality. The highest mortality was produced by hexane and chloroform extracts of seeds at 4 mg/ml(96.9 and 93.8%, respectively), with LC50 values of 1.85 mg/ml and 0.54 mg/ml, respectively. Fractions of both seed extracts were isolated by gravity column chromatography over silica gel and analyzed for their active compounds. Eight fractions of the hexane extract and six fractions of the chloroform extract from I. pauciflora seeds, exhibited larvicidal effects at 1 mg/ml (mortality from 33.3 to 88.9% and from 47.2 to 77%, respectively). Changes in larval weight were observed as compared with the control group. Phytochemical analysis through GC-MS and H1 NMR revealed the presence of fatty acids and aldehydes in the active fractions. These results indicate that the bioactive extracts from the seed of I. pauciflora can induce lethal toxicity in S. frugiperda larvae or affect the weight of the surviving larvae

Comment on "Evidence from acoustic imaging for submarine volcanic activity in 2012 off the west coast of El Hierro (Canary Islands, Spain)" by Pérez NM, Somoza L, Hernández PA, González de Vallejo L, León R, Sagiya T, Biain A, González FJ, Medialdea T, Barrancos J, Ibáñez J, Sumino H, Nogami K and Romero C [Bull Volcanol (2014) 76:882-896]

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A Two-Hybrid Assay to Study Protein Interactions within the Secretory Pathway

Interactions of transcriptional activators are difficult to study using transcription-based two-hybrid assays due to potent activation resulting in false positives. Here we report the development of the Golgi two-hybrid (G2H), a method that interrogates protein interactions within the Golgi, where transcriptional activators can be assayed with negligible background. The G2H relies on cell surface glycosylation to report extracellularly on protein-protein interactions occurring within the secretory pathway. In the G2H, protein pairs are fused to modular domains of the reporter glycosyltransferase, Och1p, and proper cell wall formation due to Och1p activity is observed only when a pair of proteins interacts. Cells containing interacting protein pairs are identified by selectable phenotypes associated with Och1p activity and proper cell wall formation: cells that have interacting proteins grow under selective conditions and display weak wheat germ agglutinin (WGA) binding by flow cytometry, whereas cells that lack interacting proteins display stunted growth and strong WGA binding. Using this assay, we detected the interaction between transcription factor MyoD and its binding partner Id2. Interfering mutations along the MyoD:Id2 interaction interface ablated signal in the G2H assay. Furthermore, we used the G2H to detect interactions of the activation domain of Gal4p with a variety of binding partners. Finally, selective conditions were used to enrich for cells encoding interacting partners. The G2H detects protein-protein interactions that cannot be identified via traditional two-hybrid methods and should be broadly useful for probing previously inaccessible subsets of the interactome, including transcriptional activators and proteins that traffic through the secretory pathway

Performance of the CMS Cathode Strip Chambers with Cosmic Rays

The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device in the CMS endcaps. Their performance has been evaluated using data taken during a cosmic ray run in fall 2008. Measured noise levels are low, with the number of noisy channels well below 1%. Coordinate resolution was measured for all types of chambers, and fall in the range 47 microns to 243 microns. The efficiencies for local charged track triggers, for hit and for segments reconstruction were measured, and are above 99%. The timing resolution per layer is approximately 5 ns

Galactic cold cores VIII. Filament formation and evolution: Filament properties in context with evolutionary models

Context. The onset of star formation is intimately linked with the presence of massive unstable filamentary structures. These filaments are therefore key for theoretical models that aim to reproduce the observed characteristics of the star formation process in the Galaxy.Aims. As part of the filament study carried out by the Herschel Galactic Cold Cores Key Programme, here we study and discuss the filament properties presented in GCC VII (Paper I) in context with theoretical models of filament formation and evolution.Methods. A conservatively selected sample of filaments located at a distance D < 500 pc was extracted from the GCC fields with the getfilaments algorithm. The physical structure of the filaments was quantified according to two main components: the central (Gaussian) region of the filament (core component), and the power-law-like region dominating the filament column density profile at larger radii (wing component). The properties and behaviour of these components relative to the total linear mass density of the filament and the column density of its environment were compared with the predictions from theoretical models describing the evolution of filaments under gravity-dominated conditions.Results. The feasibility of a transition from a subcritical to supercritical state by accretion at any given time is dependent on the combined effect of filament intrinsic properties and environmental conditions. Reasonably self-gravitating (high M-line,M-core) filaments in dense environments (Av greater than or similar to 3 mag) can become supercritical on timescales of t similar to 1 Myr by accreting mass at constant or decreasing width. The trend of increasing M-line,M-tot (M-line,M-core and M-line,M-wing) and ridge A(v) with background for the filament population also indicates that the precursors of star-forming filaments evolve coevally with their environment. The simultaneous increase of environment and filament Av explains the observed association between dense environments and high Mlille,co values, and it argues against filaments remaining in constant single-pressure equilibrium states. The simultaneous growth of filament and background in locations with efficient mass assembly, predicted in numerical models of filaments in collapsing clouds, presents a suitable scenario for the fulfillment of the combined filament mass-environment criterium that is in quantitative agreement with Herschel observations

Long-term microdystrophin gene therapy is effective in a canine model of Duchenne muscular dystrophy

Duchenne muscular dystrophy (DMD) is an incurable X-linked muscle-wasting disease caused by mutations in the dystrophin gene. Gene therapy using highly functional microdystrophin genes and recombinant adeno-associated virus (rAAV) vectors is an attractive strategy to treat DMD. Here we show that locoregional and systemic delivery of a rAAV2/8 vector expressing a canine microdystrophin (cMD1) is effective in restoring dystrophin expression and stabilizing clinical symptoms in studies performed on a total of 12 treated golden retriever muscular dystrophy (GRMD) dogs. Locoregional delivery induces high levels of microdystrophin expression in limb musculature and significant amelioration of histological and functional parameters. Systemic intravenous administration without immunosuppression results in significant and sustained levels of microdystrophin in skeletal muscles and reduces dystrophic symptoms for over 2 years. No toxicity or adverse immune consequences of vector administration are observed. These studies indicate safety and efficacy of systemic rAAV-cMD1 delivery in a large animal model of DMD, and pave the way towards clinical trials of rAAV-microdystrophin gene therapy in DMD patients

Conditional Transgenesis Using Dimerizable Cre (DiCre)

Cre recombinase is extensively used to engineer the genome of experimental animals. However, its usefulness is still limited by the lack of an efficient temporal control over its activity. We have recently developed a conceptually new approach to regulate Cre recombinase, that we have called Dimerizable Cre or DiCre. It is based on splitting Cre into two inactive moieties and fusing them to FKBP12 (FK506-binding protein) and FRB (binding domain of the FKBP12-rapamycin associated protein), respectively. These latter can be efficiently hetero-dimerized by rapamycin, leading to the reinstatement of Cre activity. We have been able to show, using in vitro approaches, that this ligand-induced dimerization is an efficient way to regulate Cre activity, and presents a low background activity together with a high efficiency of recombination following dimerization. To test the in vivo performance of this system, we have, in the present work, knocked-in DiCre into the Rosa26 locus of mice. To evaluate the performance of the DiCre system, mice have been mated with indicator mice (Z/EG or R26R) and Cre-induced recombination was examined following activation of DiCre by rapamycin during embryonic development or after birth of progenies. No recombination could be observed in the absence of treatment of the animals, indicating a lack of background activity of DiCre in the absence of rapamycin. Postnatal rapamycin treatment (one to five daily injection, 10 mg/kg i.p) induced recombination in a number of different tissues of progenies such as liver, heart, kidney, muscle, etc. On the other hand, recombination was at a very low level following in utero treatment of DiCre×R26R mice. In conclusion, DiCre has indeed the potentiality to be used to establish conditional Cre-deleter mice. An added advantage of this system is that, contrary to other modulatable Cre systems, it offers the possibility of obtaining regulated recombination in a combinatorial manner, i.e. induce recombination at any desired time-point specifically in cells characterized by the simultaneous expression of two different promoters

The Submarine Volcano Eruption off El Hierro Island: Effects on the Scattering Migrant Biota and the Evolution of the Pelagic Communities

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Adeno-Associated Viral Vector-Mediated Transgene Expression Is Independent of DNA Methylation in Primate Liver and Skeletal Muscle

Recombinant adeno-associated viral (rAAV) vectors can support long-term transgene expression in quiescent tissues. Intramuscular (IM) administration of a single-stranded AAV vector (ssAAV) in the nonhuman primate (NHP) results in a peak protein level at 2–3 months, followed by a decrease over several months before reaching a steady-state. To investigate transgene expression and vector genome persistence, we previously demonstrated that rAAV vector genomes associate with histones and form a chromatin structure in NHP skeletal muscle more than one year after injection. In the mammalian nucleus, chromatin remodeling via epigenetic modifications plays key role in transcriptional regulation. Among those, CpG hyper-methylation of promoters is a known hallmark of gene silencing. To assess the involvement of DNA methylation on the transgene expression, we injected NHP via the IM or the intravenous (IV) route with a recombinant ssAAV2/1 vector. The expression cassette contains the transgene under the transcriptional control of the constitutive Rous Sarcoma Virus promoter (RSVp). Total DNA isolated from NHP muscle and liver biopsies from 1 to 37 months post-injection was treated with sodium bisulfite and subsequently analyzed by pyrosequencing. No significant CpG methylation of the RSVp was found in rAAV virions or in vector DNA isolated from NHP transduced tissues. Direct de novo DNA methylation appears not to be involved in repressing transgene expression in NHP after gene transfer mediated by ssAAV vectors. The study presented here examines host/vector interactions and the impact on transgene expression in a clinically relevant model